JPH09311327A - Liquid crystal display - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make faults of orientation processings to be generated by the overlappings of coloring layers so as not affect influences to a display by allowing coloring layers of different colors to be overlapped with each other on light shielding areas in adjacent pixel areas and shifting centers of overlapped widths to pixel area sides nearer to an orientation starting direction than centers of widths of the light shielding parts. SOLUTION: Liquid crystal 130 is held in between an array substrate 101 and a counter substrate 102. On the array substrate 101, signal lines 23 are formed on the whole of the surface of the substrate so as to be orthogonally crossed with scanning lines via a gate insulating film 50 and thin film transistors(TFT) are formed at intersetions of the scanning lines and the signal lines and coloring layers 40 are formed so as to cover TFTs. At this time, reflections of the signal lines are prevented by forming the coloring layers 40 while overlapping them on the signals. Then, these overlapped parts are formed by being more shifted to the orientation starting direction than centers of wiring widths. Thus, areas of orientation faults due to differences of levels of the overlappings are made so as not to reach display areas.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device, and more particularly to a colored layer formed on an array substrate.

[0002]

2. Description of the Related Art In a liquid crystal display device, liquid crystal is sandwiched between an array substrate including switching elements such as thin film transistors and pixel electrodes and a counter substrate including common electrodes and the like. Conventionally, the colored layer has been formed on the counter substrate, but a technique for forming the colored layer on the array substrate has been developed in order to prevent a decrease in the aperture ratio due to a margin for the bonding accuracy of the substrates.

Further, in order to obtain a higher aperture ratio, an insulating colored layer is formed between the wiring of the scanning line and the signal line and the pixel electrode, and the wiring and the pixel electrode are three-dimensionally separated, and the wiring is wired. A structure has been developed in which the wiring doubles as a light-shielding film by stacking the pixel electrode on.

FIG. 7 shows a plan view of an array substrate on which a colored layer is formed. FIG. 8 is a sectional view taken along the line AA ′ of FIG. In FIG. 8A, the coloring layers in the adjacent pixel regions are formed without overlapping. In this case, there is a portion where the colored layer is not formed on the signal line. In general, a metal having a high reflectance such as Al is used for the signal line, which causes a reduction in contrast when the signal line is used as a light shielding film.

Further, in FIG. 8B, the colored layers in the adjacent pixel regions are formed to overlap each other. In this case, since the signal line is entirely covered with the colored layer, the reduction in contrast due to the reflection of the signal line does not pose a problem. However, a step is generated in the overlapping portion, and when the alignment process is performed, the back side of the step is shaded, and the alignment process is not performed, which causes display failure.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a liquid crystal display device in which a defective alignment treatment caused by overlapping of colored layers does not affect the display.

[0007]

According to the present invention, there is provided a first substrate, a light-shielding portion formed on the first substrate, a colored layer formed corresponding to a predetermined pixel region, and the substrate. A first electrode substrate having a first electrode formed thereon and a first alignment film formed on the first substrate; a second substrate; and a second substrate on the second substrate. A second electrode substrate having the formed second electrode and a second alignment film formed on the second substrate; and the first electrode substrate and the second electrode substrate. In the liquid crystal display device having a sandwiched liquid crystal, colored layers having different colors in adjacent pixel regions are overlapped with a width in a corresponding region on the light shielding portion,
The liquid crystal display device is characterized in that the center of the overlapping width is displaced from the center of the width of the light shielding portion toward the pixel region closer to the alignment start direction.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings. (Embodiment 1) FIG. 1 is a plan view showing a liquid crystal display device of this embodiment. 2A is a sectional view taken along the line AA ′ in FIG. 1, and FIG. 2B is a sectional view taken along the line BB ′ in FIG.

The structure of the liquid crystal display device is the array substrate 101.
The liquid crystal 130 is sandwiched between the counter substrate 102 and the counter substrate 102. In the configuration of the array substrate 101, the scanning line 20 is formed on the substrate 10, and the auxiliary capacitance line 22 is further formed in parallel with the scanning line 20. A signal line 23 is formed on the entire surface of the substrate via the gate insulating film 50 so as to be orthogonal to the scanning line 20. Then, a thin film transistor (TFT: Thin Film) is provided at the intersection of the scanning line 20 and the signal line 23.
Transistor) is formed. This thin film transistor has a structure in which a gate electrode 21 branched from the scanning line 20, a gate insulating film 50 on the gate electrode 21, a semiconductor layer 30, and an etching stopper layer 51 are stacked, an ohmic contact layer 31, and a drain electrode 2 are stacked.
4, the source electrode 25 is laminated.

A colored layer 40 is formed so as to cover the TFT. This colored layer 40 is R (red), G
The three colors (green) and B (blue) are formed in stripes in parallel with the signal lines 23 and overlap the colored layers 40 in the pixel regions adjacent to each other on the signal lines 23.

The pixel electrode 27 is formed on the colored layer 40.
Are formed, and the pixel electrode 27 and the source electrode 25 are connected through the opening of the colored layer 40. An auxiliary electrode 26 is formed on the auxiliary capacitance line 22 in the same layer as the signal line 23 with a gate insulating film 50 interposed therebetween.
6 and the pixel electrode 27 are also connected through the opening.

Then, an alignment film 111 is formed on the entire surface to form the array substrate 101. The counter substrate 102 is the substrate 1
The counter electrode 12 and the alignment film 112 are formed on the entire main surface of the first electrode 1.

Next, the manufacturing steps will be sequentially described. First, the array substrate 101 will be described. For example, tantalum is deposited to a thickness of 300 nm on one main surface of the substrate 10 made of glass by a sputtering method, and then patterned into a predetermined shape to form the scanning line 20, the gate electrode 21 which is a part of the scanning line, and the auxiliary capacitance line 22. Form.

Next, 350 nm of silicon oxide that becomes the gate insulating film 50 and 50 n of a-Si layer that becomes the semiconductor layer 30 are formed.
m, silicon nitride to be the etching stopper layer 51 is 1
50 nm is coated on the entire substrate by the plasma CVD method. After that, only silicon nitride is first patterned to form the etching stopper layer 51. Then, the n + -type a-Si layer to be the ohmic contact layer 31 is formed to 5
The semiconductor layer 30 and the ohmic contact layer 31 are formed by film-forming with a thickness of 0 nm and patterning together with the a-Si layer. Then, for example, aluminum is sputtered 500 times.
Then, the signal line 23, the drain electrode 24, the source electrode 25, and the auxiliary electrode 26 are formed. In this embodiment, the width of the signal line 23 is about 10 μm.

Next, a 1.5 μm colored layer 40 made of acrylic resin is applied to the entire surface and photo-etched to form a predetermined shape in the order of R, G and B in this embodiment.

At this time, by overlapping the colored layer 40 on the signal line 23, the reflection of the signal line 23 can be prevented and the contrast can be prevented from lowering. However, when the colored layers 40 are overlapped with each other, a step is generated, and when the alignment process is performed later, a shadow region is formed due to the step, which may cause alignment failure. Therefore, by placing the shadow area within the line width of the signal line 23, the display is not adversely affected. In this embodiment, as shown in FIG. 2A, the overlapping portion is formed so as to be shifted to the left of the center of the wiring width. In this case, the shift to the left is because the alignment direction shown in FIG. 1 is performed from the upper left side. However, in the present embodiment, the overlapping portion is located on the side (left side) completely close to the alignment start direction from the center of the wiring width, but even if the overlapping portion is out of the center of the wiring width, Compare the center of the width and the position,
It suffices if the center of the overlapping width is displaced toward the side closer to the alignment start direction.

Next, each colored layer 40 has a pixel electrode 27.
An opening 60 for connecting the source electrode 25 and the pixel electrode 27 to the auxiliary electrode 26 is formed. Then, for example, ITO (Indium Tin Oxide) is coated to a thickness of 100 nm by a sputtering method and patterned to form the pixel electrode 27. In this embodiment, the pixel electrode 27 defines the opening by wiring by overlapping with the signal line 23 and the scanning line 20, and the wiring also serves as a light shielding film.

The coloring layer 40 determines the relationship between the dielectric constant and the thickness so that the parasitic capacitance formed in the overlapping portion of the pixel electrode, the signal line 23 and the scanning line 20 does not affect the display.

Finally, an alignment film 111 made of low temperature cure type polyimide is formed on the entire surface. Then, the surface of the alignment film 111 is rubbed in a predetermined direction with a cloth or the like to perform the alignment treatment.

In this way, the desired array substrate 101 can be obtained. Next, the counter substrate 102 will be described. For example, ITO is formed on one main surface of the substrate 11 made of glass.
And the array substrate 10 is formed.
An alignment film 112 similar to that of No. 1 is formed. Then, the alignment film 112 is subjected to an alignment treatment in an alignment direction that is deviated from the alignment direction of the alignment film 111 of the array substrate 101 by 90 degrees. In this way, the counter substrate 102 is obtained.

Then, the array substrate 101 and the counter substrate 10
2 and 2 are arranged so that the surfaces on which the respective alignment films are formed face each other, and are bonded together by a sealing material except for the injection port. Further, the liquid crystal 130 is injected into the gap from the injection port,
Seal the inlet.

Then, the array substrate 101 and the counter substrate 10
Polarizing plates 121 and 122 are attached to the outer surface of each of the two. At this time, the polarization axes of the polarizing plate 121 of the array substrate 101 and the polarizing plate 122 of the counter substrate 102 are displaced by 90 degrees.

Then, a backlight is arranged on the array substrate 101 side to obtain a liquid crystal display device. (Embodiment 2) FIG. 3 is a plan view of one pixel of the liquid crystal display device of this embodiment, and FIG. 4 is a sectional view taken along the line AA 'in FIG.

The structure of this embodiment is a pattern in which the pixel electrodes 27 do not overlap the scanning lines 20 and the signal lines 23 as in the first embodiment. The gap between the pixel electrode 27 and the signal line 23 is shielded by the shield electrode 22a integrated with the auxiliary capacitance line 22.

The distance between the pixel electrode 27 and the scanning line 20 is shielded by a stripe-shaped light shielding film 41 provided on the counter substrate 102 or the array substrate 101. In the case of the present embodiment, the adjacent colored layers 40 are overlapped on the shield electrode 22a. The overlapping portion is formed on the pixel region side closer to the alignment start direction than the center of the width of the shield electrode. Other configurations are the same as those in the first embodiment.

According to this embodiment, the scanning line 20 and the signal line 2
3 and the pixel electrode 27 do not overlap with each other and there is no fear of parasitic capacitance. Therefore, the coloring layer 40 may be formed of a material and a thickness suitable for desired characteristics without considering the dielectric constant and the thickness of the coloring layer 40. it can. (Embodiment 3) In this embodiment, the coloring layers 40 in the adjacent pixel regions are used.
The remaining colored layer 40 of one color is further formed on the overlapping portion.
Is provided in an island shape to form a columnar spacer.

For example, when the colored layers are formed in the order of R, G, and B, B is formed after R and G are overlapped in a portion where the R pixel region and the G pixel region are adjacent to each other. In the process, B is also formed in an island shape in this portion. Further, in the portion where the G pixel region and the B pixel region are adjacent to each other, R is formed into an island shape in this portion in the step of first forming R, and thereafter,
Overlap this part in the order of G and B. Further, in a portion where the R pixel region and the B pixel region are adjacent to each other, R
After forming, G is formed in an island shape in this portion in the step of forming G, and finally B is overlapped.

Also in the case of this embodiment, as in the first and second embodiments, the center of the overlapping width of the three layers is formed so as to be shifted to the pixel region side closer to the alignment start direction than the center of the wiring width. Further, although the above-mentioned embodiments are all of the inverted stagger type, the present invention can be modified in various ways such as a stagger type and a coplanar type.

[0029]

According to the present invention, the colored layers in the adjacent pixel regions overlap each other on the wiring, and the overlapping portion is formed deviating from the center of the wiring width in the alignment start direction, so that there is a step difference in the overlapping. It is possible to prevent the poorly oriented region from reaching the display region.

[Brief description of drawings]

FIG. 1 is a plan view showing one pixel of a liquid crystal display device according to a first embodiment of the present invention.

2A is a sectional view taken along the line AA ′ in FIG. 1, and FIG. 2B is a sectional view taken along the line BB ′ in FIG.

FIG. 3 is a plan view showing one pixel of a liquid crystal display device according to a second embodiment of the present invention.

FIG. 4 is a cross-sectional view taken along the line A-A ′ in FIG.

FIG. 5 is a plan view showing one pixel of a liquid crystal display device according to a third embodiment of the present invention.

6 is a cross-sectional view taken along the line A-A ′ in FIG.

FIG. 7 is a plan view showing one pixel of a conventional liquid crystal display device.

8A and 8B are both AA ′ in FIG.
It is an example of a section in.

[Explanation of symbols]

 10, 11 substrate 20 scanning line 22 auxiliary capacitance line 22a shield electrode 23 signal line 27 pixel electrode 40 colored layer 101 array substrate 102 counter substrate 130 liquid crystal

Claims (7)

[Claims] 1. A first substrate, a light-shielding portion formed on the first substrate, a colored layer formed corresponding to a predetermined pixel region, and a first substrate formed on the substrate. A first electrode substrate having an electrode and a first alignment film formed on the first substrate; a second substrate; and a second electrode formed on the second substrate. A second alignment film formed on the second substrate,
In a liquid crystal display device having a second electrode substrate having a liquid crystal sandwiched between the first electrode substrate and the second electrode substrate, the colored layers having different colors in adjacent pixel regions are A liquid crystal display device, characterized in that they overlap each other with a width in a corresponding region on a light-shielding portion, and the center of the overlapping width is displaced from the center of the width of the light-shielding portion toward the pixel region closer to the alignment start direction. 2. The liquid crystal display device according to claim 1, wherein the overlapping portion of the colored layers having different colors is formed on the pixel region side closer to the alignment start direction than the center of the width of the light shielding portion. 3. The liquid crystal display device according to claim 1, wherein the light shielding portion is made of metal. 4. The first electrode substrate has a plurality of scanning lines formed in parallel on the first substrate and a signal formed in parallel to the scanning lines via an insulating film. A line, a thin film transistor formed in the vicinity of an intersection of the scanning line and the signal line, and a pixel electrode connected to the thin film transistor, wherein the scanning line and the signal line serve as a light-shielding portion. The liquid crystal display device according to claim 1, 2, or 3. 5. The first electrode substrate includes a plurality of scanning lines formed in parallel on the first substrate, an auxiliary capacitance line, and
A shield electrode extending from the auxiliary capacitance line, a signal line formed in parallel with the scanning line through an insulating film, and a signal line formed in the vicinity of an intersection of the scanning line and the signal line The liquid crystal display device according to claim 1, further comprising a thin film transistor and a pixel electrode connected to the thin film transistor, wherein the shield electrode is a part of the light shielding portion. 6. The liquid crystal display device according to claim 1, wherein the overlapping portion of the colored layers also serves as a spacer for keeping a distance between the first electrode substrate and the second electrode substrate. 7. The liquid crystal display device according to claim 6, wherein the overlapping portion of the colored layers has a region in which three or more layers are laminated.